You could also use 0.06% methylene blue in 0.5M sodium acetate pH 5.2, other buffers may work as well. This is less sensitive than ethidium bromide, but still appplicable to all kinds of nucleic acids. Methylene blue produces high background staining, so prepare to wash your gel several times in water.

I think ethidium bromide is suitable for you need.

ethidium bromide is a good choice but it is biohazard

But SYBR-Green acn also help you.....sometime primer dimer can also picked up by this stain